This brings back memories of the declaration on the pound note that used to say "I promise to pay the bearer one pound", or words to that effect. Is that tautology or wha'?

As a postscript, on the way back I tried to use a pound coin picked up in NI which had a thistle motif on it (presumably issued for use in Scotland) in the environs of London, and it was refused, even though it had the Queen's head on the other side and coinage is at least notionally issued by the sovereign state rather than by a bank.

All the more reason to spend it all on drink before it goes out of fashion.